/Engine/Source/Editor/UnrealEd/Classes/Editor/EditorEngine.h
Above function but called a frame later, to stop PIE login from happening from a network callback
virtual void OnLoginPIEComplete_Deferred ( int32 LocalUserNum, bool bWasSuccessful, [FString](API\Runtime\Core\Containers\FString) ErrorString, [FPieLoginStruct](API\Editor\UnrealEd\FPieLoginStruct) DataStruct )